The verify_hostname_of_cert function in the certificate checking feature in IO-Socket-SSL (IO::Socket::SSL) 1.14 through 1.25 only matches the prefix of a hostname when no wildcard is used, which allows remote attackers to bypass the hostname check for a certificate.

• http://www.openwall.com/lists/oss-security/2009/08/31/4
• http://www.openwall.com/lists/oss-security/2009/08/28/1
• http://cpansearch.perl.org/src/SULLR/IO-Socket-SSL-1.30/Changes
• http://www.openwall.com/lists/oss-security/2009/08/29/1
• http://lists.opensuse.org/opensuse-security-announce/2009-09/msg00001.html
• http://www.vupen.com/english/advisories/2011/0118
• http://www.gentoo.org/security/en/glsa/glsa-201101-06.xml
• http://secunia.com/advisories/42893